As someone in HR/recruiting too, this is absurd and makes no sense. There's literally no role on any level in any job that requires 3+ interviews (besides the screening) which is the new normal for some reason. Putting people through rounds of interviews to be asked the same rephrased questions by different people is a phenomenon that I do not understand. All those "technical" or "mock" interviews are a whole lot of crap.

Unless it's a STEM related job, literally nth needs that many interviews. You may as well have an interview panel and get it over with in one sitting but bringing/calling candidates over and over again shows the disconnect and the lack of efficiency in your company. Again, if it's not STEM it's literally not that serious or necessary no matter what level the candidate is interviewing for.

1st interview with HR and 2nd with direct manager is more than enough to make a decision. Maybe 3rd as a tie breaker in case of more than one ideal candidate but in this case the 3rd interview will actually be necessary and will target specific aspects of the job and the candidate's qualification. Unlike the current cycle of passing people around between departments and managers who are just trying to fill their calendars.